Action Points

Note that there were no serious drug-related adverse effects in either group although the intrauterine system was partially or completely expelled in four patients, and approximately 10 patients in each group did not complete the study.

Over the course of six cycles, median reduction in blood loss among women with heavy menstrual bleeding who used the intrauterine system was 128.8 mL compared with a decrease of just 17.8 mL in those taking medroxyprogesterone (P<0.001), according to Andrew M. Kaunitz, MD, of the University of Florida in Jacksonville, and colleagues.

Moreover, the proportion of women treated successfully -- defined as blood loss below 80mL and a 50% or more decrease from baseline -- was significantly higher in the intrauterine system group (84.8% versus 22.2%, P<0.001), the researchers reported in the September issue of Obstetrics & Gynecology.

The intrauterine system works by providing a constant release of levonorgestrel directly into the uterine cavity and suppressing the endometrium.

Because a recent small study found the IUD was better at reducing bleeding than oral therapy, Kaunitz and colleagues conducted a larger, multicenter trial to assess blood loss using the objective alkaline hematin method (in which hemoglobin is extracted and measured from sanitary materials).

They included 165 women 18 and older with idiopathic heavy bleeding, randomly assigning them to 10 mg/day of medroxyprogesterone for 10 consecutive days in each cycle, or to placement of the IUD.

After three months, blood loss had decreased by 115.1 mL and by 3.2 mL in the intrauterine system and oral treatment groups, respectively (P<0.001).

After six cycles, the percentage decrease in mean blood loss in the intrauterine system group was 70.8% compared with 21.5% in the oral treatment group (P<0.001).

By the study's end, fewer than 30% of those in the oral treatment group had experienced a 50% decrease in blood loss; 80% of those using the IUD had a 70% or more decrease.

Adverse events were reported by 42.6% of the women. Most were mild to moderate in severity, and included headache in 16.3% of the IUD group and 11% of those in the oral therapy groups.

Bacterial vaginitis occurred in 11.3% and 3.7% of the intrauterine device and medroxyprogesterone groups, respectively, and urinary tract infections developed in 7.5% and 3.7%.

The IUD was completely expelled by two women and partially expelled in two others.

There were no serious drug-related adverse events, and no uterine perforations or pregnancies occurred.

The investigators noted that they used the highest dose of oral medroxyprogesterone and the longest duration of treatment per cycle approved for abnormal uterine bleeding in the U.S.

Other studies using the oral drug at higher doses have had better results, they acknowledged.

"Although a higher dose and longer duration of treatment may have improved results with oral medroxyprogesterone acetate, it is not likely that the treatment would have been superior to the more than 70% reduction observed with the levonorgestrel-releasing intrauterine system," they wrote.

Also in favor of the intrauterine device is the fact that it is licensed for up to five years of use, it can reduce the need for hysterectomy, and is cost-effective, according to the investigators.

"This trial adds to a substantial body of evidence demonstrating the utility of the levonorgestrel-releasing intrauterine system in the treatment of heavy menstrual bleeding," they concluded.

The study was supported by Bayer Schering Pharma AG.

The lead author is on the scientific advisory board and acts as a consultant for Bayer Schering Pharma AG, and his university receives funding from the company for conducting clinical trials.

Another author reported receiving research and consulting payments from Bayer Healthcare and Bayer Schering Pharma AG, and two others are employees of Bayer Schering Pharma Oy/AG.